Our research aims at an understanding of lipid metabolism and atherosclerosis through a concerted, multi-discipline approach. Research objectives are: the study of the basic processes of cholesterol and lipoprotein metabolism, transport, and turnover, as related to atherosclerosis; and the long-term clinical evaluation of the partial ileal bypass operation, and adjuvant measures, in the management of patients with hyperlipidemia and atherosclerosis. Our methods include: (1) Clinical evaluation, utilizing serial lipid profile studies; electrocardiography, including treadmill exercise tracings; vectorcardiography; and selective peripheral and coronary arteriography. (2) Test animal and clinical studies of cholesterol absorption, cholesterol and bile acid excretion, cholesterol turnover, and index of cholesterol synthesis, and mathematically calculated cholesterol pool sizes. (3) Sterol extraction from blood, serum, and body tissues. (4) Gross and microscopic studies of animal atherosclerosis. (5) Bioengineering methods, such as viscosity determination at different rates of shear, using a cone-plate viscometer.